* gnu/services/mcron.scm (list-of-gexps?): New predicate.
(mcron-configuration): Rewrite using define-configuration.
[log?, log-format]: New fields.
(mcron-shepherd-services): Invoke mcron with the --log and --log-format
arguments when log? is #t,
(generate-doc): New procedure.
* doc/guix.texi (Scheduled Job Execution): Update doc.
(Mcron Home Service): Likewise.
* gnu/home/services/mcron.scm: Keep in sync with the above changes to
gnu/services/mcron.scm.
9b21cd2e9a